UHF RFID 태그 칩용 저전력, 저면적 비동기식 EEPROM 설계

백승면,이재형,송성영,김종희,박문훈,하판봉,김영희,Baek, Seung-Myun,Lee, Jae-Hyung,Song, Sung-Young,Kim, Jong-Hee,Park, Mu-Hun,Ha, Pan-Bong,Kim, Young-Hee 한국정보통신학회 2007 한국정보통신학회논문지 Vol.11 No.12

본 논문에서는 $0.18{\mu}m$의 EEPROM cell을 사용하여 수동형 UHF RFID 태그 칩에 사용되는 저전력, 저면적의 1Kbits 비동기식 EEPROM IP를 설계하였다. 저면적 회로 설계 기술로는 $0.18{\mu}m$ EEPROM 공정을 이용하여 비동기식 EEPROM IP를 설계하므로 command buffer와 address buffer를 제거하였고 separate I/O 방식을 사용하므로 tri-state 데이터 출력 버퍼(data output buffer)를 제거하였다. 그리고 저전압(low voltage)의 VDD에서 EEPROM cell이 필요로 하는 고전압(high voltage)인 VPP와 VPPL 전압을 안정적으로 공급하기 위해 기존의 PN 접합 다이오드 대신 Schottky 다이오드를 사용한 Dickson 전하펌프를 설계하므로 전하펌프의 펌핑단(pumping stage)의 수를 줄여 전하펌프가 차지하는 면적을 줄였다. 저전력 회로 설계 기술로 Dickson 전하 펌프(charge pump)를 이용하여 VPP generator를 만들고 Dickson 전하펌프의 임의의 노드 전압을 이용하여 프로그램과 지우기 모드에서 각각 필요로 하는 VPPL 전압을 선택하도록 하게 해주는 VPPL 전원 스위칭 회로를 제안하여 쓰기전류(write current)를 줄이므로 저전력 EEPROM IP를 구현하였다. $0.18{\mu}m$ 공정을 이용하여 설계된 비동기식 EEPROM용 테스트 칩은 제작 중에 있으며, 비동기식 1Kbits EEPROM의 레이아웃 면적은 $554.8{\times}306.9{\mu}m2$로 동기식 1Kbits EEPROM에 비해 레이아웃면적을 11% 정도 줄였다. In this paper, a low-power and small-area asynchronous 1 kilobit EEPROM for passive UHF RFID tag chips is designed with $0.18{\mu}m$ EEPROM cells. As small area solutions, command and address buffers are removed since we design asynchronous I/O interface and data output buffer is also removed by using separate I/O. To supply stably high voltages VPP and VPPL used in the cell array from low voltage VDD, Dickson charge pump is designed with schottky diodes instead of a PN junction diodes. On that account, we can decrease the number of stages of the charge pump, which can decrease layout area of charge pump. As a low-power solution, we can reduce write current by using the proposed VPPL power switching circuit which selects each needed voltage at either program or write mode. A test chip of asynchronous 1 kilobit EEPROM is fabricated, and its layout area is $554.8{\times}306.9{\mu}m2$., 11% smaller than its synchronous counterpart.

UHF RFID 태그 칩용 저전력 EEPROM설계

이원재,이재형,박경환,이정환,임규호,강형근,고봉진,박무훈,하판봉,김영희,Yi, Won-Jae,Lee, Jae-Hyung,Park, Kyung-Hwan,Lee, Jung-Hwan,Lim, Gyu-Ho,Kang, Hyung-Geun,Ko, Bong-Jin,Park, Mu-Hun,Ha, Pan-Bong,Kim, Young-Hee 한국정보통신학회 2006 한국정보통신학회논문지 Vol.10 No.3

본 논문에서 는 플래쉬 셀을 사용하여 수동형 UHF RFID 태그 칩에 사용되는 저전력 1Kb 동기식 EEPROM을 설계하였다. 저전력 EEPROM을 구현하기 위한 방법으로 다음과 같은 4가지 방법을 제안하였다. 첫째, VDD(=1.5V)와 VDDP(=2.5V)의 이중 전원 공급전압 방식을 사용하였고, 둘째, 동기식 회로 설계에서 클럭(clock) 신호가 계속 클럭킹(clocking)으로 인한 스위칭 전류(switching current)가 흐르는 것을 막기 위해 CKE(Clock Enable) 신호를 사용하였다. 셋째, 읽기 사이클에서 전류 센싱(current sensing) 방식 대신 저전력 소모를 갖는 clocked inverter를 사용한 센싱 방식을 사용하였으며, 넷째, 쓰기 모드시 Voltage-up 변환기(converter) 회로를 사용하여 기준전압 발생기(Reference Voltage Generator)에는 저전압인 VDD를 사용할 수 있도록 하여 전력 소모를 줄일 수가 있었다. $0.25{\mu}m$ EEPROM 공정을 이용하여 칩을 제작하였으며, 1Kb EEPROM을 설계한 결과 읽기 모드와 쓰기 모드 시에 소모되는 전력은 각각 $4.25{\mu}W$와 $25{\mu}W$이고, 레이아웃 면적(layout area)은 $646.3\times657.68{\mu}m^2$이다. In this paper, a low-power 1Kb synchronous EEPROM is designed with flash cells for passive UHF RFID tag chips. To make a low-power EEPROM, four techniques are newly proposed. Firstly, dual power supply voltages VDD(1.5V) and VDDP(2.5V), are used. Secondly, CKE signal is used to remove switching current due to clocking of synchronous circuits. Thirdly, a low-speed but low-power sensing scheme using clocked inverters is used instead of the conventional current sensing method. Lastly, the low-voltage, VDD for the reference voltage generator is supplied by using the Voltage-up converter in write cycle. An EEPROM is fabricated with the $0.25{\mu}m$ EEPROM process. Simulation results show that power dissipations are $4.25{\mu}W$ in the read cycle and $25{\mu}W$ in the write cycle, respectively. The layout area is $646.3\times657.68{\mu}m^2$.

Risk Assessment of 5-Chloro-2-Methylisothiazol-3(2H)-One/2-Methylisothiazol-3(2H)-One (CMIT/MIT) Used as a Preservative in Cosmetics

Kim, Min Kook,Kim, Kyu-Bong,Lee, Joo Young,Kwack, Seung Jun,Kwon, Yong Chan,Kang, Ji Soo,Kim, Hyung Sik,Lee, Byung-Mu Korean Society of ToxicologyKorea Environmental Mu 2019 Toxicological Research Vol.35 No.2

The mixture of 5-chloro-2-methylisothiazol-3(2H)-one (CMIT) and 2-methylisothiazol-3(2H)-one (MIT), CMIT/MIT, is a preservative in cosmetics. CMIT/MIT is a highly effective preservative; however, it is also a commonly known skin sensitizer. Therefore, in the present study, a risk assessment for safety management of CMIT/MIT was conducted on products containing 0.0015% of CMIT/MIT, which is the maximum MIT level allowed in current products. The no observed adverse effect level (NOAEL) for CMIT/MIT was 2.8 mg/kg bw/day obtained from a two-generation reproductive toxicity test, and the skin sensitization toxicity standard value for CMIT/MIT, or the no expected sensitization induction level (NESIL), was $1.25{\mu}g/cm^2/day$ in humans. According to a calculation of body exposure to cosmetics use, the systemic exposure dosage (SED) was calculated as 0.00423 mg/kg bw/day when leave-on and rinse-off products were considered. Additionally, the consumer exposure level (CEL) amounted to $0.77512{\mu}g/cm^2/day$ for all representative cosmetics and $0.00584{\mu}g/cm^2/day$ for rinse-off products only. As a result, the non-cancer margin of safety (MOS) was calculated as 633, and CMIT/MIT was determined to be safe when all representative cosmetics were evaluated. In addition, the skin sensitization acceptable exposure level (AEL)/CEL was calculated as 0.00538 for all representative cosmetics and 2.14225 for rinse-off products; thus, CMIT/MIT was considered a skin sensitizer when all representative cosmetics were evaluated. Current regulations indicate that CMIT/MIT can only be used at concentrations 0.0015% or less and is prohibited from use in other cosmetics products. According to the results of this risk assessment, the CMIT/MIT regulatory values currently used in cosmetics are evaluated as appropriate.

X-ray 이미지 센서용 싱글 픽셀 포톤 카운터 설계

백승면,김태호,강형근,전성채,진승오,허영,하판봉,박무훈,김영희,Baek, Seung-Myun,Kim, Tae-Ho,Kang, Hyung-Geun,Jeon, Sung-Chae,Jin, Seung-Oh,Huh, Young,Ha, Pan-Bong,Park, Mu-Hun,Kim, Young-Hee 한국정보통신학회 2007 한국정보통신학회논문지 Vol.11 No.2

본 논문에서는 디지털 의료 영상 및 진단 분야 그리고 산업용으로도 활용 가능한 싱글 포톤 계수형 영상센서를 $0.18{\mu}m$ triple-well CMOS(Complementary Metal Oxide Semiconductor) 공정을 사용하여 설계하였다. 설계된 Readout 칩용 싱글 픽셀은 디지털 X-ray 이미지 센서모듈을 간단화 하기 위해 단일 전원전압을 사용하였으며, Preamplifier의 출력 전압인 signal voltage(${\Delta}Vs$)를 크게 하기 위해 Folded Cascode CMOS OP amp를 이용한 Preamplifier를 설계하였으며, 기존의 Readout 칩 외부에서 인가하던 threshold voltage를 Readout 칩 내부에서 생성해 줄 수 있도록 Externally Tunable Threshold Voltage Generator 회로를 새롭게 제안하였다. 그리고, Photo Diode에서 발생하는 Dark Current Noise를 제거하기 위한 Dark Current Compensation 회로를 제안하였으며, 고속 counting이 가능하고, layout 면적이 작은 15bit LFSR(Linear Feedback Shift Resister) Counter를 설계하였다. A single pixel photon counting type image sensor which is applicable for medical diagnosis with digitally obtained image and industrial purpose has been designed with $0.18{\mu}m$ triple-well CMOS process. The designed single pixel for readout chip is able to be operated by single supply voltage to simplify digital X-ray image sensor module and a preamplifier which is consist of folded cascode CMOS operational amplifier has been designed to enlarge signal voltage(${\Delta}Vs$), the output voltage of preamplifier. And an externally tunable threshold voltage generator circuit which generates threshold voltage in the readout chip has been newly proposed against the conventional external threshold voltage supply. In addition, A dark current compensation circuit for reducing dark current noise from photo diode is proposed and 15bit LFSR(Linear Feedback Shift Resister) Counter which is able to have high counting frequency and small layout area is designed.

TFT -LCD 구동 IC용 커패시터 내장형 DC-DC 변환기 설계

임규호,강형근,이재형,손기성,조기석,백승면,성관영,이용진,박무훈,하판봉,김영희,Lim Gyu-Ho,Kang Hyung-Geun,Lee Jae-Hyung,Sohn Ki-Sung,Cho Ki-Seok,Baek Seung-Myun,Sung Kwan-Young,Li Long-Zhen,Park Mu-Hun,Ha Pan-Bong,Kim Young-Hee 한국정보통신학회 2006 한국정보통신학회논문지 Vol.10 No.7

A non-overlap boosted-clock charge pump(NBCCP) with internal pumping capacitor, an advantageous circuit from a minimizing point of TFT-LCD driver IC module, is proposed in this paper. By using the non-overlap boosted-clock swinging in 2VDC voltage, the number of pumping stages is reduced to half and a back current of pumping charge from charge pumping node to input stage is also prevented compared with conventional cross-coupled charge pump with internal pumping capacitor. As a result, pumping current of the proposed NBCCP circuit is increased more than conventional cross-coupled charge pump, and a layout area is decreased. A proposed DC-DC converter for TFT-LCD driver IC is designed with $0.18{\mu}m$ triple-well CMOS process and a test chip is in the marking. 본 논문에서는 TFT-LCD 구동 IC 모듈의 소형화측면에서 유리한 DC-DC 변환기 회로인 펌핑 커패시터 내장형 비중첩 부스트-클락 전하펌프 (Non-overlap Boosted-Clock Charge Pump: NBCCP) 회로가 제안되었다 .2VDC 전압으로 스윙하는 비중첩 부스트-클럭의 사용으로 기존의 펌핑 커패시터 내장형 크로스-커플드 전하펌프에 비해 펌핑 단의 수를 반으로 줄일 수 있었고, 전하 펌핑 노드의 펌핑된 전하가 입력 단으로 역류되는 현상을 방지하였다 . 그 결과 제안된 펌핑 커패시터 내장형 비중첩 부스트-클럭 전하펌프 회로는 기존의 펌핑 커패시터 내장형 크로스-커플드 전하펌프에 비해 펌핑 전류가 증가하였고, 레이아웃 면적은 감소되었다. 제안된 TFT-LCD 구동 IC용 DC-DC 변환기 회로를 $0.18{\mu}m$ Triple-Well CMOS 공정을 사용하여 설계하고, 테스트 칩을 제작 중에 있다.

저전압 SoC용 밴드갭 기준 전압 발생기 회로 설계

이태영,이재형,김종희,심외용,김태훈,박무훈,하판봉,김영희,Lee, Tae-Young,Lee, Jae-Hyung,Kim, Jong-Hee,Shim, Oe-Yong,Kim, Tae-Hoon,Park, Mu-Hun,Ha, Pan-Bong,Kim, Young-Hee 한국정보통신학회 2008 한국정보통신학회논문지 Vol.12 No.1

The band-gap reference voltage generator which can be operated by low voltage is proposed in this paper. The proposed BGR circuit can be realized in logic process by using parasitic NPN BJTs because a $Low-V_T$ transistors are not necessary. The proposed BGR circuit is designed and fabricated using $0.18{\mu}m$ triple-well process. The mean voltage of measured VREF is 0.72V and the three sigma$(3{\sigma})$ is 45.69mv. 본 논문에서는 $Low-V_T$ 트랜지스터가 필요 없는 로직공정으로 Parasitic NPN BJT를 이용하여 저 전압에서 동작 가능한 밴드갭 기준전압 발생기 회로를 제안하였다. $0.18{\mu}m$ triple-well 공정을 사용한 BGR회로를 측정 한 결과 VREF의 평균전압은 0.72V $3{\sigma}$는 45.69mV로 양호하게 측정되었다.

A New Histone Deacetylase Inhibitor, MHY219, Inhibits the Migration of Human Prostate Cancer Cells via HDAC1

De, Umasankar,Kundu, Soma,Patra, Nabanita,Ahn, Mee Young,Ahn, Ji Hae,Son, Ji Yeon,Yoon, Jung Hyun,Moon, Hyung Ryoung,Lee, Byung Mu,Kim, Hyung Sik The Korean Society of Applied Pharmacology 2015 Biomolecules & Therapeutics(구 응용약물학회지) Vol.23 No.5

Histone deacetylase (HDAC) inhibitors are considered novel agents for cancer chemotherapy. We previously investigated MHY219, a new HDAC inhibitor, and its potent anticancer activity in human prostate cancer cells. In the present study, we evaluated MHY219 molecular mechanisms involved in the regulation of prostate cancer cell migration. Similar to suberanilohydroxamic acid (SAHA), MHY219 inhibited HDAC1 enzyme activity in a dose-dependent manner. MHY219 cytotoxicity was higher in LNCaP ($IC_{50}=0.67{\mu}M$) than in DU145 cells ($IC_{50}=1.10{\mu}M$) and PC3 cells ($IC_{50}=5.60{\mu}M$) after 48 h of treatment. MHY219 significantly inhibited the HDAC1 protein levels in LNCaP and DU145 cells at high concentrations. However, inhibitory effects of MHY219 on HDAC proteins levels varied based on the cell type. MHY219 significantly inhibited LNCaP and DU145 cells migration by down-regulation of matrix metalloprotease-1 (MMP-1) and MMP-2 and induction of tissue inhibitor of metalloproteinases-1 (TIMP-1). These results suggest that MHY219 may potentially be used as an anticancer agent to block cancer cell migration through the repression of MMP-1 and MMP-2, which is related to the reduction of HDAC1.

넓은 전압 범위와 개선된 파워-업 특성을 가지는 밴드갭 기준전압 발생기의 스타트-업 회로

성관영,김종희,김태호,카오투안부,이재형,임규호,박무훈,하판봉,김영희,Sung, Kwang-Young,Kim, Jong-Hee,Kim, Tae-Ho,Vu, Cao Tuan,Lee, Jae-Hyung,Lim, Gyu-Ho,Park, Mu-Hum,Ha, Pan-Bong,Kim, Young-Hee 한국정보통신학회 2007 한국정보통신학회논문지 Vol.11 No.8

본 논문에서는 넓은 동작전압 범위와 저소비 전력 그리고 개선된 파워-업 특성을 가지는 캐스코드 전류 거울형 CMOS 밴드갭 기준전압 발생기의 스타트-업 회로를 제안하였다. 새롭게 제안된 스타트-업 회로는 기존의 스타트-업 회로에 비해 안정적인 파워-업 특성을 가지며 공급전압(VDDA)이 높아지더라도 밴드갭 기준전압 발생기 회로의 동작에 영향을 미치지 않는 것을 모의실험을 통하여 확인하였고 $0.18{\mu}m$ tripple-well CMOS 공정을 이용하여 테스트 칩을 제작하고 측정하였다. 측정 된 기준전압 Vref는 평균값이 738mV이고 $3{\sigma}$는 29.88mV이다. A start-up circuit of the bandgap reference voltage generator of cascode current mirror type with wide operating voltage range and enhanced power-up characteristics is proposed in the paper. It is confirmed by simulation that the newly proposed start-up circuit does not affect the operation of the bandgap reference voltage generatory even though the supply voltage(VDDA) is higher and has more stable power-up characteristic than the conventional start-up circuit. Test chips are designed and fabricated with $0.18{\mu}m$ tripple well CMOS process and their test has been completed. The mean value of measured the reference voltage(Vref) is 738mV and The three sigma value($3{\sigma}$) is 29.88mV.

Energy 槪念形成과 學習指導에 關한 硏究

金泰亨,金成俊,卞茂永 晋州敎育大學校 科學敎育硏究所 1975 科學敎育硏究 Vol.1 No.-

For this study, a experiment school (No. of student: 591), inquired schools (No. of studert 2,214) and 180 teachers were participated. ○Contents of the study is as table 1. Table Ⅰ -------------------------------------------------------------------------------------------- Concept Basic concept Unit School year level -------------------------------------------------------------------------------------------- Ⅵ 6. Energy is accompanied with chemical ○Chemical change 6 change of matter. -------------------------------------------------------------------------------------------- Ⅴ 5. An energy changes into another ○Exchange of energy 5 energy. -------------------------------------------------------------------------------------------- Ⅳ 4. Light is one kind of energy. ○Properties of light -------------------------------------------------------------------------------------------- Ⅲ 3. Heat brings a change of substance. ○Heat and change of 4 substance 3 -------------------------------------------------------------------------------------------- Ⅱ 2. Electricity has energy. ○Electric circuit 3 -------------------------------------------------------------------------------------------- Ⅰ 1. Earth receives energy from the sun. ○Light and shadow 2 -------------------------------------------------------------------------------------------- Basic concept : Energy is always accompanied with natural penomena. -------------------------------------------------------------------------------------------- ○Major subjects of the study. 1) Is it possible to decide the knowledge order of energy concept by the analysis and investigation for the relation between recognition development progress of student and scientific concept formation of student about heat, light, electricity, sound, dynamic (potential and kinetic) and chemical energy? 2) What is the answer for the problem of present teaching method for energy concept formation in primary school science? Data for the study are as follows : Table Ⅱ -------------------------------------------------------------------------------------------- School year 2 3 4 5 6 ------------------------------------------------------------------------------ Unit Light & Electric Properties Exchange Chemical Average(%) Subject\ shadow circuit of light of energy change -------------------------------------------------------------------------------------------- Experiment 71.71% 59.58 65.97 74.83 67.56 69.13 (116) (120) (118) (118) (119) (591) -------------------------------------------------------------------------------------------- Inquired 66.24 46.33 52.82 55.89 57.25 55.71 (414) (461) (431) (452) (450) (2,214) -------------------------------------------------------------------------------------------- * Figures in parenthesis is the number of students. Difference of the means of two populations on table Ⅱ is 13.43%. And it is recognized that experiment school subject is prior in score to that of inquired school and the experiment application is significant. Table Ⅲ -------------------------------------------------------------------------------------------- Unit 2 3 4 5 6 -------- Ability ----------------------------------------------------------- Average(%) Light & Electric Properties Energy Chemical Subject shadow circuit of light exchange change -------------------------------------------------------------------------------------------- Scientific 86.68 69.58 68.26 75.50 70.00 74.00 concept Experi- ----------------------------------------------------------------------------------- Scientific 73.75 58.17 78.09 73.05 81.26 72.86 ment attitude ----------------------------------------------------------------------------------- Scientific 69.50 72.77 72.62 74.06 57.94 57.79 ability -------------------------------------------------------------------------------------------- Scientific 73.58 59.95 51.49 60.96 58.76 60.95 concept Inquired ----------------------------------------------------------------------------------- Scientific 64.84 44.17 57.17 62.05 67.43 59.13 attitude ----------------------------------------------------------------------------------- Scientific 57.11 43.83 52.01 59.16 52.89 53.00 ability -------------------------------------------------------------------------------------------- Difference of mean scores in scientific concept formation is 13.05%, for scientific attitude, 13.73% and for scientific ability, 4.79%, according to the table Ⅲ above. Score of experiment school is prior to that of inquired school and it means that students grow up and progress under the influence of educational environment. A little difference of mean scores in scientific ability is considered as a result of systematic and intensive teaching. The result of inquired school for light and shadow unit, is 66.24%. This is recognized that student's experienced concrete thinking, which was made already before when he did not attend a school yet, was cohered with his daily life and it brought active to learn and improvement of formation. 46.23% of electricity circuit unit is concluded that student are not enough to think yet for practical operation of it. Energy concept formation of student, found out from this study, is the order of Sound energy →Light energy →Electric energy →Movement energy → Heat energy →Chemical energy. Study results for problem 2) are 51.31% in mountain & farm village, 54.71% in fishing village, 55.29% in suburb and 68.57% in urban area. This data may indicate a problem of environment and education. Table Ⅳ. -------------------------------------------------------------------------------------------- School Location Mountain & Fishing Suburb Urban area Total year Unit farm village village -------------------------------------------------------------------------------------------- 2 Light & shadow 59.09 67.83 57.68 97.38 66.24(414) -------------------------------------------------------------------------------------------- 3 Electricity circuit 43.06 44.17 47.16 52.29 66.33(467) -------------------------------------------------------------------------------------------- 4 Properties of light 51.27 52.59 56.45 55.27 52.82(431) -------------------------------------------------------------------------------------------- 5 Energy & exchange 55.35 63.91 57.34 65.88 55.89(452) -------------------------------------------------------------------------------------------- 6 Chemical exchange 49.80 45.05* 60.84 71.96 57.25**(450) -------------------------------------------------------------------------------------------- Total 51.31 54.71 55.29 68.57 -------------------------------------------------------------------------------------------- It is emphasized to formulate experimental process and materials and carriculum involving, selection of teaching materials for location, selection of concept suitable to recognition progress of student, precise experimental guidance, step by step with-out jump, series, and order. ○Response of the teachers who participated in primary school science course, are 76.11% as difficult, 54.45% as too much curriculum but teaching time short. Teacing activities which have the student fully understood through lesson guidance of reliable predicting results for unknown matter, are required. The study results are summarized as follows : 1) In concept formation about energy, light, sound, heat and chemical energy was fixed but electricity & dynamic energy was infixed and weak. 2) An order of energy concept recognition, considering growth and progress of student, is sound-light-electricity-dynamic-heat-chemical energy. 3) Results of lesson for energy concept indicates attitude and ability are poor, regardless of school year and location. 4) Responses of primary school teachers for the science are that curriculum is difficult but destination is hopeful and teaching material is short. 5) They want individual examination, such as test of experimental process with material.

스포츠 현장에서 사고 분쟁해결을 위한 법적 구조 및 그 효용성 분석

박형상,육조영,김우규,이재봉,유관호,이무연,박태민,이신언 한국스포츠리서치 2005 한국 스포츠 리서치 Vol.16 No.2

1. The purpose of this study is to reflect reality of sports to legal structure. This author classified types of sports related accidents as match accidents, school accidents, leisure and living sports accidents. Out of such accidents common factors such as 'the provider of virtue' and 'user' could be deduced and this author reviewed what kinds of obligations must be shouldered by these people respectively. In particular this author stressed the fact that disproportionate emphasis is placed on malfeasance in disposition of dispute over the sports accidents. Malfeasance is a method for seeking relief through money after the accident. However default in an obligation enables supplementary completion when it is not performed or imperfectly performed. Thus if object which must be performed is providing safety then it is possible to secure safety prior to accident. Furthermore at such time mistake of the debtor can not become a factor. For this reason this line of thinking has the following merits: (1) In comparison with constitution of malfeasance default of an obligation has long prescription. It seems that such fact was a motivation for saving obligation for safety consideration by making it fall under the principle of faith. (2) Default of an obligation is not an obligation for ordinary attention which is cause of malfeasance but it takes up issue with obligation for attention required for performance. Game organization, sponsor and spectators etc. shares certain sense of identity and are demanded to have manners. As method for evaluation of such relationship of faith it may be possible to impose a special kind of obligation for attention and it will be close to constitution of default of an obligation. (3) Imposing obligation for provision clarifies that such responsibility belongs to game organizations promoting sports to which anyone can participates or to national or public organizations, sponsor, schools which induced such sports as a part of its educational programs, installer who made people use it as leisure facility or person in charge for its management. (4) It is also applicable to umpires, players or spectators who use field of sports. It is possible to reflect reality whereby these people specifically relate themselves to sports. In consequence it will be possible to make people feel the necessity of expanding the principals of sports from 'doers' to 'watchers.' (5) The obligation of provision is an obligation under the principle of faith therefore mutual negotiation may be expected to clarify such fact. It may be also evaluated by effectuation of users' self-determining right. 2. If the above mentioned structure is provided then, although it is limited to sports, students who are subjects of instruction, seminar attendants, and furthermore players who finished games may be obligated to bear responsibility for safety consideration under the principle of faith. Accordingly level of relief for considerable number of victims may be increased as cases of treating even borrowed materials as default of obligation being expanded. 3. As scope of responsibility becomes more clearer it will be possible to prevent disputes while securing more safety as rules and regulations become more clearly enacted or new contract is signed or existing contract is revised.